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Harvey Leroy Karman (1924–2008)

Harvey Karman was an abortionist, inventor, and activist for safe abortion techniques in the US during the twentieth century. Karman developed the Karman cannula, a flexible soft tube used for vacuum aspiration abortions. Karman traveled extensively throughout the US to educate healthcare providers on how to administer safe abortions. He also traveled to Bangladesh, India, China, and other developing nations to promote safe and simple abortion techniques that anyone could perform without previous medical training.

Format: Articles

Subject: People

The Role of the Notch Signaling Pathway in Myogenesis

Among other functions, the Notch signaling pathway forestalls the process of myogenesis in animals. The Notch signaling pathway is a pathway in animals by which two adjacent cells within an organism use a protein named Notch to mechanically interact with each other. Myogenesis is the formation of muscle that occurs throughout an animal's development, from embryo to the end of life. The cellular precursors of skeletal muscle originate in somites that form along the dorsal side of the organism.

Format: Articles

Subject: Theories, Processes

Wilhelm His, Sr. (1831-1904)

Wilhelm His, Sr. was born on 9 July 1831 in Basel, Switzerland, to Katharina La Roche and Eduard His. He began his medical studies at Basel in 1849 and later transferred to the University of Bern during the winter semester of 1849-1850. A year later, His arrived at the University of Berlin, where he studied under Johannes Müller and Robert Remak. For his clinical training, His attended the University of Würzburg from 1852-1853.

Format: Articles

Subject: People

Wilhelm Roux (1850-1924)

Wilhelm Roux was a nineteenth-century experimental embryologist who was best known for pioneering Entwicklungsmechanik, or developmental mechanics. Roux was born in Jena, Germany, on 9 June 1850, the only son of Clotilde Baumbach and a university fencing master, F. A. Wilhelm Ludwig Roux. Roux described himself as an aloof child, but when he was fourteen he cultivated a passion for science that was encouraged by the director at Oberrealschule in Meiningen.

Format: Articles

Subject: People

Slime mold development video by John Tyler Bonner

This video is composed of a sequence of time lapse films created by John Tyler Bonner in the 1940s to show the life cycle of the cellular slime mold, Dictyostelium discoideum. As only the second person to study slime molds, Bonner frequently encountered audiences who had never heard of, let alone seen, the unusual organism. He therefore decided to create a film to present at seminars in order to introduce his object of study. Bonner created the video for his senior thesis at Harvard University with the help of photographer Frank Smith.

Format: Video

Subject: Organisms

Walter Jakob Gehring (1939-2014)

Walter Jakob Gehring discovered the homeobox, a DNA segment found in a specific cluster of genes that determine the body plan of animals, plants, and fungi. Gehring identified the homeobox in 1983, with the help of colleagues while isolating the Antennapedia (Antp) gene in fruit flies (Drosophila) at the University of Basel in Basel, Switzerland. Hox genes, a family of genes that have the homeobox, determine the head-to-tail (anterior-posterior) body axis of both vertebrates and invertebrates.

Format: Articles

Subject: People

Digit Regeneration Is Regulated by Msx1 and BMP4 in Fetal Mice (2003), by Manjong Han et al.

In the early 2000s, Manjong Han, Xiaodang Yang, Jennifer Farrington, and Ken Muneoka investigated how genes and proteins in fetal mice (Mus musculus) influenced those fetal mice to regenerate severed toes at Tulane University in New Orleans, Louisiana. The group used hind limbs from mice to show how the gene Msx1 (Homeobox 7) functions in regenerating amputated digits.

Format: Articles

Subject: Experiments

Light Therapy for Neonatal Jaundice

Light therapy, also called phototherapy, exposes infants with jaundice, a yellowing of the skin and eyes, to artificial or natural light to break down the buildup of bilirubin pigment in the blood. Bilirubin is an orange to red pigment produced when red blood cells break down, which causes infants to turn into a yellowish color. Small amounts of bilirubin in the blood are normal, but when there is an accumulation of excess bilirubin pigment, the body deposits the excess bilirubin in the layer of fat beneath the skin.

Format: Articles

Subject: Technologies

Beadle and Tatum's 1941 Experiments with Neurospora Revealed that Genes Produce Enzymes

This illustration shows George Beadle and Edward Tatum's experiments with Neurospora crassa that indicated that single genes produce single enzymes. The pair conducted the experiments at Stanford University in Palo Alto, California. Enzymes are types of proteins that can catalyze reactions inside cells, reactions that produce a number of things, including nutrients that the cell needs. Neurospora crassa is a species of mold that grows on bread.

Format: Graphics

Subject: Theories, Experiments

Gordon Watkins Douglas (1921-2000)

Gordon Watkins Douglas researched cervical cancer, breach delivery, and treatment of high blood pressure during pregnancy in the US during the twentieth century. He worked primarily at Bellevue Hospital Center in New York, New York. While at Bellevue, he worked with William E. Studdiford to develop treatments for women who contracted infections as a result of illegal abortions performed throughout the US in unsterile environments.

Format: Articles

Subject: People

Ponseti's Treatment for Congenital Clubfoot (1963)

In 1963, Ignacio Ponseti and Eugene Smoley experimentally determined an effective and minimally invasive method of treating congenital clubfoot. Congenital clubfoot is a disorder in which a newborn’s foot is rigidly turned inwards and upwards. During the early 1960s, orthopedists often relied on invasive surgical procedures to treat clubfoot.

Format: Articles

Subject: Experiments

"Mitochondrial DNA and Human Evolution" (1987), by Rebecca Louise Cann, Mark Stoneking, and Allan Charles Wilson

In 1987 Rebecca Louise Cann, Mark Stoneking, and Allan Charles Wilson published Mitochondrial DNA and Human Evolution in the journal Nature. The authors compared mitochondrial DNA from different human populations worldwide, and from those comparisons they argued that all human populations had a common ancestor in Africa around 200,000 years ago. Mitochondria DNA (mtDNA) is a small circular genome found in the subcellular organelles, called mitochondria.

Format: Articles

Subject: Publications, Theories

Beadle's One Gene-One Enzyme Hypothesis

Between 1934 and 1945, George Beadle developed a hypothesis that each gene within the chromosomes of organisms each produced one enzyme. Enzymes are types of proteins that can catalyze reactions inside cells, and the figure shows that each enzyme controls a stage in a series of biochemical reactions. The top box in this figure represents a normal process of enzyme production and biochemical reactions, and the bottom box shows how Beadle's experiments affected the normal biochemical process.

Format: Graphics

Subject: Theories, Processes

Isaacson v. Horne (2013)

In the 2013 case Isaacson v. Horne, the US Court of Appeals in the Ninth Circuit ruled that Arizona House Bill (HB) 2036, which prohibited abortions after twenty weeks of gestation, was unconstitutional. The Arizona State Legislature passed the law in 2012, which was then challenged by three physicians who filed a lawsuit against the state, arguing that the law violated women's constitutionally protected rights to abortions, rights that may only be infringed once fetuses are viable outside of the womb.

Format: Articles

Subject: Legal

Thomas Joseph King Jr. (1921-2000)

Thomas Joseph King Jr. was a developmental biologist who, with fellow scientist Robert Briggs, pioneered a method of transplanting nuclei from blastula cells into fresh egg cells lacking nuclei. This method, dubbed nuclear transplantation, facilitated King's studies on cancer cell development. King's work was instrumental for the development of cloning of fish, insects, and mammals.

Format: Articles

Subject: People

James David Ebert (1921-2001)

James David Ebert studied the developmental processes of chicks and of viruses in the US during the twentieth century. He also helped build and grow many research institutions, such as the Department of Embryology in the Carnegie Institution of Washington in Baltimore, Maryland and the Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts. When few biologists studied the biochemistry of embryos, Ebert built programs and courses around the foci of biochemistry and genetics, especially with regards to embryology.

Format: Articles

Subject: People

Infantile Autism: The Syndrome and Its Implications for a Neural Theory of Behavior (1964), by Bernard Rimland

Infantile Autism: The Syndrome and Its Implications for a Neural Theory of Behavior (hereafter Infantile Autism) is a book written by Bernard Rimland, published in 1964. The book proposed a theory to explain the causes of autism. The book also synthesized research into autism and used Rimland's neural theory, described in the book, as a theory to explain some aspects of behavior, intelligence, and abnormality.

Format: Articles

Subject: Publications

"The Cell-Theory" (1853), by Thomas Henry Huxley

The Cell-Theory was written by Thomas Henry Huxley in Britain and published in 1853 by The British and Foreign Medico-Chirurgical Review. The twenty-two page article reviews twelve works on cell theory, including those in Germany by Caspar Friedrich Wolff in the eighteenth century and by Karl Ernst von Baer in the nineteenth century. Huxley spends much of The Cell-Theory on a cell theory proposed in the late 1830s by Matthias Schleiden and Theodor Schwann in Germany.

Format: Articles

Subject: Publications

Gonzales v. Carhart (2007)

In Gonzales v. Carhart (2007), the US Supreme Court held in a five-to-four decision that the 2003 Partial-Birth Abortion Ban Act passed by the US Congress was constitutional. Although the Court previously ruled in Stenberg v. Carhart (2000) that a Nebraska law that prohibited partial-birth abortions was unconstitutional, Gonzales reversed this decision. Gonzales created the precedent that anyone who delivers and kills a living fetus could be subject to legal consequences, unless he or she performed the procedure to save the life of the mother.

Format: Articles

Subject: Legal, Reproduction

Stenberg v. Carhart (2000)

In Stenberg v. Carhart, the US Supreme Court ruled on 28 June 2000 that a Nebraska law banning partial birth abortions was unconstitutional. Though the US Supreme Court case Roe v. Wade in 1973 had set a precedent that constitutionally protected abortions, some states established limitations on certain types of abortion procedures. When NebraskaÕs state government criminalized partial birth abortions, physician LeRoy Carhart challenged the constitutionality of the case. Don Stenberg, an Attorney General located in Lincoln, Nebraska, represented the state of Nebraska.

Format: Articles

Subject: Legal

Making Visible Embryos (2008- ), by Tatjana Buklijaz and Nick Hopwood

Making Visible Embryos is a 2008 online exhibition of embryos authored and designed by Tatjana Buklijaz and Nick Hopwood who work in the Department of History and Philosophy of Science at the University of Cambridge. Hopwood's research on the history of Ziegler wax models and the use of visual aids to promote the teaching and learning of science is well known.

Format: Articles

Subject: Organizations, Outreach

Embryos in Wax (2002), by Nick Hopwood

Embryos in Wax: Models from the Ziegler Studio is a history of embryo wax modeling written by science historian Nick Hopwood. Published by the Whipple Museum of the History of Science University of Cambridge and the Institute of the History of Medicine University of Bern, 2002, the book, like the wax models, helps exemplify the visual and material culture of science.

Format: Articles

Subject: Publications

Hermaphrodites and the Medical Invention of Sex (1998), by Alice Domurat Dreger

Hermaphrodites and the Medical Invention of Sex, by historian of science Alice Domurat Dreger, was published in 1998 by Harvard University Press. In the book, Dreger describes how many doctors and scientists treated human hermaphrodites from the late nineteenth century to the early twentieth century. She states that during this time period, many physicians and scientists struggled to determine the nature sex, and to support a classification of sex as male or female, many physicians and scientists resorted to viewing a person's gonads for identification of his or her sex.

Format: Articles

Subject: Publications, Theories, Disorders

Endoderm

Endoderm is one of the germ layers-- aggregates of cells that organize early during embryonic life and from which all organs and tissues develop. All animals, with the exception of sponges, form either two or three germ layers through a process known as gastrulation. During gastrulation, a ball of cells transforms into a two-layered embryo made of an inner layer of endoderm and an outer layer of ectoderm. In more complex organisms, like vertebrates, these two primary germ layers interact to give rise to a third germ layer, called mesoderm.

Format: Articles

Subject: Processes

Robert Lanza (1956- )

During the twentieth and twenty-first centuries, Robert Paul Lanza studied embryonic stem cells, tissues,
and endangered species as chief scientific officer of Advanced Cell
Technology, Incorporated in Worcester, Massachusetts. Lanza's team cloned
the endangered species of gaur Bos gaurus.
Although the gaur did not survive long, Lanza successfully cloned
another cow-like creature, called the banteng
(Bos
javanicus). Lanza also worked on cloning human embryos
to harvest stem cells, which could be used to treat dieases. While

Format: Articles

Subject: People